The present invention relates to an uplink resource scheduling method, a wireless base station and a mobile station, and more specifically, the present invention relates to an uplink resource scheduling method for a Non-Orthogonal Multiple Access (NOMA) system, a wireless base station and a mobile station.
In a Long Term Evolution (LTE) communication system and an LTE-Advanced communication system, when a mobile station (UE) needs to perform uplink transmission, it transmits a scheduling request signaling to a wireless base station (eNB), to obtain information of uplink resources serviceable for the mobile station from the wireless base station. In a communication system using a NOMA wireless access technology, it is proposed to distinguish a plurality of mobile stations by a transmission power, so that when uplink data are transmitted, data of different mobile stations are multiplexed to the same sub-band for transmission. Thereby, the number of the mobile stations for which the wireless base station can support simultaneous scheduling is increased.
In Release 8, the wireless base station notifies the uplink resources allocated to each mobile station, by respectively generating and transmitting a resource allocation signaling indicating the uplink resources allocated to the mobile stations for the mobile stations transmitting the scheduling requests thereto in a cell managed by the wireless base station. However, since in this method, the resource allocation signaling is respectively transmitted to the mobile stations, large signaling overhead is incurred. Further, in the NOMA communication system, with increased number of the mobile stations for which the wireless base station can support simultaneous scheduling, the signaling overhead incurred by the resource allocation signaling will further increase.
It has been proposed to notify the mobile station of the allocated uplink resources by two-stage signaling, to solve the problem of large signaling overhead. Specifically, first-stage signaling is cell dedicated signaling, wherein the cell dedicated signaling may include information indicating different uplink resources respectively allocated to the plurality of mobile stations in the cell managed by the wireless base station, which transmit the scheduling request to the wireless base station. The wireless base station may broadcast the cell dedicated signaling, so that all the mobile stations in the cell receive the signaling and decode it. In addition, second-stage signaling is mobile station dedicated signaling, wherein the wireless base station can respectively generate and transmit mobile station dedicated signaling for respective mobile stations managed thereby, and each mobile station dedicated signaling can indicate a position of information of the uplink resources allocated to a mobile station in the cell in the cell dedicated signaling. However, it is necessary to enable the mobile station with a worst channel state in the cell to receive the cell dedicated signaling being broadcast, so a coding rate of the cell dedicated signaling is determined based on the worst channel state of the mobile station, which results in unnecessary signaling overhead for the mobile stations with a better channel state. In addition, it is necessary for the mobile station to perform blind decoding twice in order to respectively obtain the cell dedicated signaling and the mobile station dedicated signaling, which increases a burden of the mobile station.